Radio receiver



June 22, 1943.

A. H. COOPER RADIO RECEIVER Filed Juno 7 1939 2 Sheets-Sheet l INVENTOR.Riff/UP HENRY COUPZI )KZW ATTORNEY.

June 22, 1943. Q A. H. COOPER 2,322,280

RADIO RECEIVER Filed June '7, 1939 2 Sheets-Sheet 2 INVENTOR. men/u;l/i/VIV (awn A TORNEY.

Patented June 22, 1943 UNITED STATES PATENT OFFICE RADIO RECEIVERMiddlesex, Britain England, a company of Great Application June 7, 1939,Serial No. 277,832 In Great Britain June 17, 1938 9 Claims.

This invention relates to improvements in radio receivers which employan automatic station selecting mechanism.

Various methods of automatic station selection have been proposed inwhich, by a simple operation, such as by pressing a button or byoperating a switch, the receiver is automatically set so as to be tunedto the required transmitting station. In known forms of automatic tuningmechanism it is usually necessary to adjust the receiver manually inorder to place the receiver in a condition for long, medium orshort-wave reception. Thereafter operation of the automatic stationselecting mechanism tunes the receiver to a desired station. Thenecessity of providing, in conjunction with an automatic mechanism, amanually operated wave-change mechanism, is obviously undesirable.

The present invention obviates the necessity of the operator carryingout a manual operation, apart from an initial station selectingoperation, and provides means whereby on pressing a button or setting aswitch or operating any other form of selecting mechanism the requisitesteps for tuning the receiver, for instance adjusting a tuning condenserand wave change switch, are carried out automatically in successiverelationship.

According to the invention there is provided in radio receivers anautomatic station selection mechanism whereby a series of discrete stepsfor setting the circuit elements are carried out automatically insuccessive relationship on being initiated by a single control element.

The setting of the various circuit elements which require to be adjustedat each discrete step in the tuning operation may be carried out bymeans of a single motor, and it is according to the operation of thismotor that the successive steps in the tuning are controlled. Theoperation of the motor may be initiated by the operation of one of aplurality of elements such as pushbuttons, which may be placed wheredesired, such as at a position remote from the radio receiver which itis desired to operate. Operation of any of these push-buttons serves toadjust the receiver to a predetermined station. Operation of apush-button also serves in one form of the invention to adjust the wavechange mechanism in a manner appropriate to the selected station.

For the purpose of explaining the invention more in detail referencewill be made to the accompanying drawings which illustratediagrammatically by way of example means for carrying out the presentinvention, and in which the same reference numerals indicate similarparts:

Figure 1 is a circuit diagram showing means for setting the tuningcondenser and the wavechange switch of a radio receiver'according to oneform of the present invention;

Figure 2 shows a modification of the embodiment of the invention shownin Figure 1 and which employs solenoids external to the motor fordisplacing the shaft of the motor axially;

Figure 3 shows a modification of the invention in which the individualoperations for tuning the radio receiver are selected by a series ofmagnetic clutches. The embodiment shown in this figure has means forcontrolling the volume of the radio receiver as well as adjusting thetuning condenser and the wave-change drive.

Figure 1 of the drawings illustrates the invention as applied to a radioreceiver in which predetermined stations can be selected at will by theoperation of one of a plurality of push buttons, operation of the pushbuttons also serving to actuate a wave range changing mechanism so as toadjust the receiver to the appropriate wave range according to thestation selected. Adjustment of the receiver is effected by an electricmotor I the armature shaft 2 of which is provided at the ends withpinions 3 and 4 each of which is capable of meshingwith one or other ofgear wheels 6 and l. The gear wheel 6 rotates a station selecting drum 8which, in turn, is connected to a variable tuning condenser 10. The drum8 is of known form and is provided with conducting zones and aninsulating zone 9 and bearing on the surface of the drum is a pluralityof contact arms the relative positions of which with respect to theinsulating zone 9 determine the extent to which the condenser I0 isrotated. The gear wheel 1 rotates a wave range selecting drum l I havingconducting zones and an insulating zone [2 and bearing on the surface ofthe drum II is a plurality of contact arms which serve to complete acircuit through the drum II, and when any one of the contact armsengages the insulating zone the circuit through the drum is broken andin this position the range change switch 13 to which the drum II isconnected is adjusted to the appropriate position. The contact armsbearing on the drums 8 and H are connected by the leads shown to pairsof contacts indicated respectively by the numerals I4, l5, each pair ofcontacts being associated with a push button, as shown, and when any oneof the push buttons is operated each pair of contacts l4 and I5associated with such push button is closed for the purpose hereinafterreferred to. The pushbuttons are labeled B1, B2, B3 and B4 and comprisewedgeshaped elements which act upon depression to close the switches l4and I5.

The armature of the motor I is arranged to be axially movable wherebythe pinions 3 and 4 can selectively engage the gear wheels I5 and I,movement of the armature to the left serving to couple the pinion 3 tothe gear wheel 6 and disconnecting the pinion 4 from the gear wheel Iand co1npressing the spring I6. The motor I is of known form and is suchthat when a sufficiently high voltage is applied to the stator windingsa solenoid action accurs causing the armature to move axially againstthe tension of the spring I6. The circuit to the motor I is completedthrough two circuits, one associated with the drum 8 and the contactarms S3 S4, S5 and So, which bear thereon and the other through the drumI I and the contact arms W1, W2 and W3, which bear on drum II. Thecircuits from drum I l include resistances I1 and I8 which serveinitially to permit of a high voltage to be applied to the motor ashereinafter referred to. On depressing one of the push buttons, forinstance B1, the two pairs of contacts I4 and I5 associated therewithare closed and a circuit is completed from the contacts I4 and I5through the drums 8 and II thus energising the motor with a high voltagecausing the armature to be moved into a position in which the pinion 3engages the gear wheel 6. Rotation of the motor thus rotates the tuningcondenser I until the contact arm S, associated with B1 the push buttondepressed engages the insulating zone 9, thus breaking the circuitthrough the drum 8. Breaking of this circuit removes the high voltagefrom the motor and permits of a lower voltage to be applied theretothrough the drum II which remains stationary during rotation of the drum8. Removal of the high voltage from the motor permits the armature shaftto move axially under the action of the spring I6 disengaging the pinion3 and gear wheel 6 and causing engagement of the pinion 4 and gear wheelI. The voltage which is now applied to the motor is insufficient toovercome the tension of the spring I6 but is sufficient to causerotation of the armature. The armature thus continues to rotate drivingthe drum II and the switch I3 until the contact associated with thepush-button depressed engages the insulating zone I2 when the circuitthrough the drum II is broken thus disconnecting the supply from themotor I. In this manner the switch I3 is adjusted to the positionappropriate to the selected station. The contacts which bear on the drum8 may be adjustably arranged in known manner o that the operator canadjust the receiver to enable any desired stations to be obtained ondepressing the push buttons. In order to enable the wave change switchI3 to be likewise adjusted according to the stations which can beselected, the leads from the contacts I which are in circuit with thedrum II are adjustably connected to socket bars I9, and 2| into whichany of the leads associated with the contacts I5 can be engaged so thatif the operator desires to re-adjust the receiver the contactsassociated with the drum 8 are suitably adjusted and then the leads fromthe contacts I5 are plugged into the bars I5, 20 or 2| according towhether the adjusted station is either a long, medium or short wavestation.

The arrangement shown in Figure 1 operates as follows:

Assuming that the push button B2 is depressed, it will be noted that thetwo switches I4 and I5,

I9, 20 and H.

associated therewith, are closed due to the wedging action of the pushbutton. It is assumed that the push button B2 'moves the wedge upwardlywhen depressed. Closure of its associated switch I4 will impress uponmotor I a high voltage from source of alternating current S through thefollowing circuit: Upper terminal of source S, motor I, point Y,conductor L1, drum 8, station contact S5, closed switch I4 associatedwith push button B2, grounded bar B, to the grounded lower terminal ofsource S. This will cause the motor armature to be displaced to the leftthereby effecting disengagement of gears 4 and I and engagement of gears3 and 6. Rotation of the motor I causes the rotation of drum 8 andtuning means It]. When the drum 8 has been rotated sufficiently to bringthe insulation strip 9 in contact with station contact S5, the motorcircuit through switch I4 associated with push button B2 is broken.However, depression of push button B2 also completes the motor circuitthrough switch I5 associated with push button B2 through the followingcircuit: Upper contact of source S, motor I, point Y, resistor 11,conductor Li, drum I I, wave band brush W1, conductor L3, connectorstrip I9, conductor L2 (assumed to be connected to strip I9), closedswitch I5 associated with push button B2, grounded bar B to the groundedterminal of terminal S. Accordingly, as soon as the energization of themotor through drum 8 is broken because of insulation strip 9, the [motorwill be energized at a lower voltage through resistor IT. The lowervoltage is insufiicient to overcome the force exerted by spring I6,hence the motor armature will be forced over to the right (the positionshown) and a coupling established between pinion 4 and gear 1. Motor I,operating at the reduced voltage, rotates drum II and hence wave bandswitches I3 until insulation strip II contacts brush W1, at which timethe motor circuit will be broken and the motor stopped.

It is to be understood that the conductor L2 may be connected to any oneof the contact strips Thus, if conductor L2 is connected to contactstrip 20 the motor circuit would be es tablished through brush W2,whereas connection of conductor L2 to contact strip 2| establishes themotor circuit through brush W3. In the latter two cases the motor Iwould operate in the reverse direction through resistor I8.

Figure 2 illustrates a modification of the embodiment shown in Figure 1.In this modification the circuits from the contacts M and I5 which areoperated by the push-buttons are made through two solenoids MI and M2and their associated switches SI and S2. Operation of a push-buttoncauses the contacts such as It and I5 to complete the circuits throughthe solenoids MI and M2 and these solenoids respectively tend todisplace the shaft 2 in opposite directions, priority being given to theaction of one of these solenoids, say solenoid MI, so that the shaft isdisplaced from its neutral position to the left, and pinion 3 mesheswith gear 5, the circuit through the solenoid M2 being simultaneouslybroken by virtue of the elements of switch S2 being brought out ofcontact with each other. Rotation of the motor occurs until the contactarm associated with the push button depressed engages the insulatingzone 9 when the circuit through the drum 8, and hence through thesolenoid MI, is broken. Breaking of this circuit permits the shaft 2 toreturn to its neutral position, causing the circuit through solenoid M2and switch S2 to be completed. The shaft 2 is thereby displaced to theright causing pinion 4 to mesh with gear wheel I, and rotation of themotor occurs driving the drum H and the switch l3 until the contactassociated with the push button which is depressed engages theinsulating zone [2, when the circuit through the drum II is broken,disconnecting the supply from the motor I, and thus the switch I3 isadjusted to the position appropriate to the selected station.

In the modification illustrated in Figure 2 only one of the solenoids MIand M2 functions at any one time, the action of each of these solenoidsbeing such as to break the circuit through the other solenoid due toopening of either switch S1 or switch S2. Priority may be given to theaction of one or other of the solenoids MI and M2 so that the shaft 2has a preferred direction displacement to left or right, by means ofimpedances inserted in the circuits, by suit ably winding the solenoidsMI and M2, or else by shunts or by a commutator arrangement.

A similar shaft-operated switching function, which ensures that only onesolenoid functions at once, could be incorporated with the embodimentshown in Figure 1, to remove any adverse effect of the simultaneousapplication of high voltage for one rotation and low voltage for theother rotation.

In the embodiment of the invention shown in Figure 3, the operation ofthe push-buttons causes adjustment of the receiver through the action ofmagnetic clutches 22, 23 and 24 which serve to engage the condenserdrive, the wave range changing mechanism and the volume control driverespectively with the driving motor, the action of the magnetic clutchesbeing such that when one of them is operated the circuits through thewindings of the other clutches are broken by opening certain switchcontacts associated therewith. When any one of the push buttons isoperated each pair of contacts l4 and I5 completes the circuits throughthe operating electromagnet of the clutch 22 and, through the switchcontacts 21, the operating electromagnet of the clutch 23. As with thepreviously described embodiments priority may be given to the action ofthe electromagnet of the clutch 22 so that the gear 6 is caused to bedriven by the pinion 3 and the motor I drives the bevel gears 3 and 6and causes rotation of the drum 8 and the tuning condenser driveassociated therewith until the insulating zone 9 bears against the leadfrom the push-button which is operated. Breaking of this circuit causesgear 6 to cease to be driven by pinion 3 and allows the circuit to bemade through the switch 21 and electromagnet of the clutch 23 and causesgear I to be driven by pinion 4, thus effecting the appropriate settingof the wave-change switch associated with the drum 12.

The switch contacts 25 and 26 serves to allow of adjustment of thevolume of the receiver, and when either of these contacts is made acircuit is completed through the electromagnet of the clutch 24 and themotor is made to drive the volume control, and it may be arranged thatone of these switch contacts 25 and 26 causes the volume of the receiverto be decreased.

Priority may be given to the action of one of the clutches 22 and 23 bycausing the operating electromagnet to be suitably wound or else by theuse of impedances or shunts. The switch contacts 21, 28, 29, 30, 3| and32 may be so arranged that when current flows in the appropriate clutchwinding they are caused to become open, thus breaking the circuitsthrough the other clutch electromagnet: for example, when current flowsthrough the winding of clutch 22 switch contacts 21 and 28 may be madeto open, thus breaking the circuits through the clutch windings 23 and24.

The drums 8 and II are illustrated in the drawings as being ofcylindrical form. In a modification the drums 8 and II are of disc form.Further, in another modification the wave change switch l3 may be a coilturret, the positions of the coils being adjustable to receive thevarious wave-bands required.

In place of contacts 25 and 26 which are separate from the push-buttonsassociated with the contacts such as M and IS, the buttons may be madeto comprise suitable contact elements. For example, the buttons may bemade to comprise contacts which make connections to the contacts 25 or26 at the same time as they operate the contacts M and [5. Suchpush-buttons could be operated to set the tuning condenser andwave-change switch and raise or lower the volume of the receiver to therequired amount by the use of a single push-button The invention may becarried out by using contacts on a dial switch in place of buttons, orby contacts on sequence switches or on relays which could in turn beenergised from a point.

The embodiment shown need not be restricted to carrying out theoperations described, but may be modified to carry out a more extendedrange of operations.

I claim:

1. The combination with a pair of separately adjustable controllingelements, a single motor for operating said elements, a plurality ofindividually operable means each acting upon operation to couple themotor to one of said controlling elements and effect the operation ofthe controlling element to a predetermined position and means renderedeffective through continued operation of the selected one of saidselectively operable means and only when said last named controllingelement is in said predetermined position for disconnecting the motorfrom said first named controlling element and coupling the motor to theother of said controlling elements and efiect the operation of said lastnamed controlling element to a predetermined position.

2. In combination with a pair of adjustable elements, a first member fordetermining the position to which one of said elements is to beadjusted, a second member for determining the position to which theother of said elements is to be adjusted, a plurality of controlelements, one for each of a plurality of predetermined positions towhich said first member is to be adjusted, an electric motor having anaxially movable operating shaft, and means under the control of any oneof the control elements for first shifting the shaft in one directionand then in the other direction for successively actuating saidpositiondetermining members.

3. In combination with a plurality of adjustable shafts, a motor fordriving said shafts, a push-button instrumentality, circuit meansinterposed between said push-button instrumentality and said motor,acting upon operation of one of the push buttons to cause said motor toadjust one of said shafts to a predetermined position, and additionalcircuit means acting upon completion of the adjustment of said firstshaft for causing said motor to effect the adjustment of another of saidshafts to respectively different desired positions, said last namedcircuit means including a plurality of selectively operable switchingmeans for predetermining to which of said desired positions the lastnamed shaft is adjusted.

4. In combination with a plurality of adjustable shafts, a motor havingan axially movable operating shaft, means when said motor shaft is inone axial position for providing a driving connection between the motorshaft and one of said adjustable shafts, means when said motor shaft isin another axial position for providing a driving connection between themotor shaft and another of said adjustable shafts, a plurality ofselectively operable means, control circuit means interposed betweensaid motor and said selectively operable means, acting upon operation ofany one of said selectively operable means to axially shift said motorshaft to one of said positions whereby the motor shaft is coupled to oneof said adjustable shafts and cause the motor to adjust said adjustableshaft to a predetermined position, and means acting upon completion ofsaid shaft adjusting operation for causing said motor shaft to shift tothe other of said positions whereby the motor shaft is coupled to theother of said adjustable shafts and cause the motor to adjust said lastnamed adjustable shaft to a predetermined position.

5. In combination with a plurality of adjustable means, a motor foroperating said means, coupling means for providing a driving connectionbetween the motor shaft and one of said adjustable shafts, couplingmeans for providing a driving connection between the motor shaft andanother of said adjustable shafts, a plurality of selectively operablemeans, control circuit means interposed between said motor and saidselectively operable means, said control circuit means including asolenoid for operating said first coupling means and thereby couple themotor shaft to one of said adjustable means, said control circuit meansacting upon operation of any one of said selectively operable means tooperate said solenoid whereby the motor shaft is coupled to one of saidadjustable shafts and cause the motor to adjust said adjustable shaft toa predeand cause the motor to adjust said last named adjustable shaft toa predetermined position.

6. The arrangement described in claim 5 wherein each of said couplingmeans comprises a clutch mechanism.

7. In combination with a plurality of adjustable elements, a motor, aplurality of selectively operable means each acting upon selectiveoperation thereof to couple the motor to one of said adjustable elementand effect the movement of said adjustable elements to a predeterminedposition, and operable means acting conjointly with an operated one ofsaid selectively operable means and effective only upon adjustment ofsaid adjustable means to said predetermined position for effecting thedisconnection of the motor from said adjustable means, the coupling ofthe motor to another of said adjustable means and the movement of saidlast named adjustable means to a predetermined position.

8. In combination with a plurality of adjustable elements, a motor,motor control means ineluding shifting means for selectively couplingthe motor to any one of said adjustable elements, a plurality ofselectively operable means each acting upon selective operation thereofto effect through said control means the coupling of the motor to one ofsaid adjustable elements and the control of the operation of the motorso as to move said adjustable element to a predetermined position, andupon said element reaching said position to effect the coupling of themotor to another one of said adjustable elements and the control of theoperation of the motor so as to move the last named adjustable elementto a predetermined position.

9. In combination with a pair of separately adjustable controllingelements, a motor for operating said elements, said motor being normallycoupled to one of said elements only, a plurality of selectivelyoperable devices and means acting upon operation of one of said devicesfor disconnecting the motor from said last named element and couplingthe same to the other of said pair of elements and through operation ofthe motor effecting the adjustment of said other element to apredetermined position, and means rendered effective through thecontinued 0peration of the selected one of said selectively operabledevices and only when said last named controlling element reaches saidpredetermined position for causing the disconnection of the motor fromsaid last named controlling element and reestablishment of the couplingbetween the motor and the first named controlling element and throughoperation of the motor effecting the adjustment of said first namedcontrolling element to a predetermined position.

ARTHUR HENRY COOPER.

